Novel sulfur-containing organic phosphorus compounds and their production and use

ABSTRACT

A sulfur-containing organic phosphorus compound of the formula:   which is useful as an additive to lubricating oils and can be produced by the reaction of a compound of the formula:   D R A W I N G with a hydrocarbon group-introducing agent (wherein R1, R2 and R5 are each a hydrocarbon group, R3 and R4 are each a hydrogen atom or a hydrocarbon group and M is an alkali metal).

United States Patent 11 1 Tada et al.

1 1 Aug. 26, 1975 NOVEL SULFUR-CONTAINING ORGANIC PHOSPHORUS COMPOUNDS AND THEIR PRODUCTION AND USE [73] Assignees: Sakai Chemical Industry Co. Ltd.,

Sakai; Showa Oil Company, Ltd., Tokyo, both of Japan [22] Filed: Apr. 11, 1974 [21] App]. No.: 459,985

[30] Foreign Application Priority Data Apr. 11, 1973 Japan 48-041734 [52] US. Cl. 260/455 P; 252/466; 260/953 [51] Int. Cl. C07C 154/00 [58] Field of Search 260/455 B, 455 P [56] References Cited UNITED STATES PATENTS 2,381,483 8/1945 Blake et a1. 260/455 B 2,665,291 1/1954 Fischback 260/455 B 2,691,635 10/1954 Harris et a1. 260/455 B 2,786,009 3/1957 Pianfctti et al... 260/455 B 2,813,890 11/1957 Cyphers et a1. 260/455 B 2,839,561 6/1958 Schradcr .1 260/455 B 2,861,913 11/1958 Weglcr et a1 260/455 8 3,004,980 10/1961 Schrader 1, 260/455 P 3,180,791 4/1965 Rossi 1 v. 260/455 B 3,470,229 9/1969 Schrader et a]. 260/455 P Primary Examiner-Lewis Gotts Assistant Examiner-D. R. Phillips [57] ABSTRACT A sulfur-containing organic phosphorus compound of the formula:

which is useful as an additive to lubricating oils and can be produced by the reaction of a compound of the formula:

with a hydrocarbon group-introducing agent [wherein R', R and R are each a hydrocarbon group, R and R are each a hydrogen atom or a hydrocarbon group and M is an alkali metal].

19 Claims, No Drawings NOVEL SULFUR-CONTAINING ORGANIC PHOSPHORUS COMPOUNDS AND THEIR PRODUCTION AND USE The present invention relates to novel sulfurcontaining organic phosphorus compounds and their production and use. More particularly, it relates to sulfur-containing organic phosphorus compounds useful as additives to lubricating oils. lubricating compositions containing them and their preparation.

Recently, there has been an increasing demand for highly efficient mechanical units, and such demand is met by development of mechanical engineering, metallurgical technology progress and level up of machining accuracy. Then. higher power transmitted by compact units results in higher rotational and sliding speed and higher contact pressure on machine elements. A need for improved lubrication and lubricants is thus increased.

In general. lubricants for engines. power transmission units and the like are required to have a property preventing the seizure and wear of machine elements exposed to high contact pressure. They are also required to be hardly oxidized or decomposed so as to maintain good performances for a long period of time. In order to obtain such lubricants. various chemical ingredients such as oxidation inhibitors, corrosion inhibitors, rust inhibitors. anti-wear additives. extreme pressure additives. viscosity index improvers. pour point depressants and antifoaming agents are incorporated into refined As the hydrocarbon group. the one having not more than l2 carbon atoms is favorable. Specific examples are as follows: alkyl (eg. methyl. ethyl, propyl. isopropyl. butyl. isohutyl. pentyl. hcxyl. lisobutylethyl. octyl. Z-ethylhexyl). alkenyl (cg. allyl. crotyl). cycloalkyl (e.g. cyclopentyl, cyclohexyl). cycloalkenyl (eg. cyclopentenyl. cyclohexenyl). aralkyl (eg. benzyl. phenethyl). aryl (eg. phenyl. tolyl. naphthyl). etc.

Preferred examples of the hydrocarbon group repre' sented by the symbols R and R are alkyl and cycloalkyl. For the hydrocarbon group represented by the symbols R" and R, preferred are alkyl and alkenyl. For the symbol R alkyl, alkenyl. cycloalkyl, aralkyl and aryl are preferred examples of the hydrocarbon group.

The S-containing organic phosphorus compound [I] may be produced. for instance. by reacting a compound of the formula:

wherein M is an alkali metal and R. R R and R are each as defined above with a hydrocarbon groupintroducing agent.

The starting compound [II] is obtainable, for example. by reacting a phosphite compound with a carbonyl compound and reacting the resulting phosphonate compound with carbon disulfide and an alkali metal hy droxidc as shown in the following scheme:

wherein R', R and R are each a hydrocarbon group and R and R are each a hydrogen atom or a hydrocarbon group.

I l l wherein R. R R". R and M are each as defined above.

Namely. the phosphite compound [III] is reacted with the carbonyl compound [IV] in an approximately equimolar ratio at a temperature of 60 to l50C (preferably of to C) for a period of l to 3 hours (about 2 hours in most cases) to give the phosphonate compound {V}. The reaction can proceed in the absence of any catalyst but is more advantageously performed in the presence of a catalyst such as a tertiary amine (cg. triethylamine. tributylamine) or an alkali metal alkoxide (eg sodium ethoxide, potassium ethoxide). For increasing the solubility of the S-eontaining organic phosphorus compound [I] into oils. the hydrocarbon radicals represented by the symbols R and R in the phosphite compound [III] are preferred to be those having not less than 4 carbon atoms. Further. the carbonyl compound [1V] is favored to be formaldehyde or acctaldehydc which is good in the reactivity or any other compound which can produce either one of them on the reaction (cg. paraformaldehyde. trioxane, tetraoxanc, paraldehyde). Among them. the use of paraformaldehyde is particularly favored, because of 3 its economic availability. Other aldehydes are ketoncs (e.g. acetone. methylethylkctone. mcthylisobutylke tone) may in also used. In general. however, the reactivity of kctoncs is inferior to that of aldehyde.

The thus prepared phosphonate compound [Y] may be subjected to the subsequent reaction in the form of the reaction mixture or after separation from the reaction mixture. for instance, by washing with water or dilute aqueous alkali solution and evaporating water and volatile materials under reduced pressure therefrom.

The reaction of the phosphonate compound [V] with carbon disulfide and an alkali metal hydroxide is usu' ally effected in a molar ratio of 1 0.9 1.3 0.9 1.3 at a temperature of to 70C (preferably of to 50C) for a period of 30 to 120 minutes. Examples of the alkali metal hydroxide are sodium hydroxide, potassium hydroxide, etc. These may be employed in the t'orm of 5 to 50 aqueous solution.

As the hydrocarbon group-introducing agent, there nay be favorably employed a halogenated hydrocaruon, of which examples are alkyl halide (e.g. methyl :hloride, ethyl chloride, propyl chloride, butyl chloide, hexyl chloride, ethyl bromide, propyl bromide, nethyl iodide, ethyl iodide), alkenyl halide (e.g. allyl :hloride, crotyl chloride, hexenyl chloride, allyl bronide, allyl iodide), aralkyl halide (e.g. benzyl chloride, ihenethyl chloride, benzyl bromide, benzyl iodide), :IC.

The reaction of the compound [11] with the hydro :arbon group-introducing agent is normally effected in molar ratio of 1 0.8 1.2 at a temperature of 0 to '0C (preferably of 20 to 70C) for a period of 30 to 80 minutes. The reaction is usually carried out in waer. When desired, any water-miscible organic solvent e.g. ethanol, dioxane, tetrahydrofuran, dimethylsulfxide) may be used together with water.

For the separation of the thus produced compound 1] from the reaction mixture, it may be extracted with water-immiscible organic solvent (e.g. benzene, tolune, hexane), followed by evaporation of volatile mateals such as the solvent, the unreacted materials and 1e like in a conventional distillation procedure, e.g. nder reduced pressure at a temperature below 150C.

The thus obtained S-containing organic phosphorus Jmpound [l] is generally a yellow or orange yellow quid. It is excellent in resistance to heat, and no "iange is seen even when heated in water or hydro- 1l01'1C acid. Further, it shows a good solubility into trious oils and is wettable on the surface of various aterials such as metals, glasses, plastics and the like. he corrosive property to copper articles is extremely w. Moreover, it can improve markedly the load carryg capacity of lubricating oils. Considering these adintageous properties, the S-containing organic phosiorus compound [1] is useful as an additive to lubri- .ting oils, particularly as an additive in lubricating mpositions for improving their wear resistance propty and extreme pressure lubricating property. Beles, it is also useful as an insecticide, a herbicide, a istic stabilizer or the like.

Practical and presently preferred embodiments of s invention are illustratively shown in the following amplcs.

EXAMPLE 1 Preparation of the S-containing organic phosphorus compound [1:-R R (EH R I R l H; R I Z fiH-J In a flask equipped with a stirrer. diethyl phosphite (276 g), paraformaldehydc (purity, )2 Ci, 65 g) and tributylamine (8 g) are charged, and the resulting mixture is heated while stirring. The reaction starts at C. and

the temperature reaches to C with generation of heat. The reaction is carried out at the said temperature for 90 minutes. The reaction mixture is filtered to give diethylhydroxymethyl phosphonate (330 g).

In a flask equipped with a stirrer, the above obtained diethylhydroxy phosphonate (330 g) is charged, carbon disulfide (150 g) is added thereto, and the resultant mixture is stirred at 20C. While keeping the said temperature, 40 aqueous solution of sodium hydroxide (200 g) is dropwise added thereto. The exothermic reaction proceeds from the starting of the dropwise ad dition, and the reaction mixture becomes yellow. After about 30 minutes, the dropwise addition is finished, and the reaction is continued at 45C for 60 minutes.

To the reaction mixture, benzyl chloride (250 g) is added in about 10 minutes, and the reaction is continued at 50C for 120 minutes. The reaction mixture is extracted with benzene (600 m1), and the extract is washed three times with warm water (500 ml). After evaporation of the solvent from the benzene solution, volatile materials are distilled off at 1 10C under about 10 mmHg to give the objective compound (556 g) as a yellow liquid. The elementary analysis ofthe product is shown in Table 1.

EXAMPLE 2 Preparation of the S-containing organic phosphorus compound [1: R R" C H R CH3; R z si R5 CH CH=CH In a flask equipped with a stirrer, diethyl phosphite (138 g) and sodium ethoxide (0.4 g) are charged, and the resulting mixture is stirred. Then, methylethylketone (72 g) is dropwise added thereto, and the reaction is continued at 50C for 8 hours. After removal of the unreacted diethyl phosphite and methylethylketone by evaporation distillation under reduced pressure is carried out at C under 1 mmHg to give diethyl-orhydroxybutyl phosphonate (128 g).

In a flask equipped with a stirrer, the above obtained diethyl-a-hydroxybutyl phosphonate g) is charged, and carbon disulfide (38 g) is added thereto, and the resultant mixture is stirred at 25C. While keeping the said temperature, 40 7: aqueous solution of sodium hydroxide (50 g) is dropwise added thereto. After the dropwise addition is finished, the reaction is continued at 40C for 60 minutes.

To the reaction mixture, allyl chloride (38 g) is added, and the reaction is carried out at 45C for 60 minutes. The reaction mixture is extracted with benzene (300 ml). The extract is well washed with warm water. After evaporation of the solvent from the henzene solution, volatile materials are distilled off at 90C under about 10 mmHg to give the objective compound (131 g) as a yellow liquid. The elementary analysis of the product is shown in Table l.

EXAMPLE 3 Preparation of the Scontaining organic phosphorus compound ll: R R C H R R H; R it sl As in Example I. there is produced di-nbutylhydroxymethyl phosphonate (668 g) by the use of di-n-butyl phosphite (582 g). paraformaldehyde (purity, 92 f4; 98 g) and tributylamine (I? g). Using the above prepared di-n-butylhydroxymcthyl phosphonate (470 g). carbon disulfide (I68 g). 30 Z: aqueous solu tion of sodium hydroxide (290 g) and benzyl chloride (253 g). the reaction is effected as in Example I. The reaction mixture is extracted with n-hexane (700 ml). the extract is well washed with warm water and the solvent is removed from the n-hcxane solution by evaporation. Then. volatile materials are distilled off at 120C under 5 mmHg to give the objective compound (640 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table 1.

EXAMPLE 4 Preparation of the S-containing organic phosphorus compound ll: R' R C H R R H; R z s sl As in Example I but the reaction time being 100 minutes, there is produced diisobutylhydroxymethyl phosphonate (666 g) by the use of diisobutyl phosphite (582 g). trioxane (90 g) and triethylamine [4 g). To a mixture of diisobutylhydroxymethyl phosphonate (448 g) and carbon disulfide 152 g), 40 71 aqueous solution of sodium hydroxide (200 g) is dropwise added thereto under the same condition as in Example I. The reaction is effected at 35C for 80 minutes. Then. benzyl chloride (253 g) is added thereto, and the reaction is performed at 50C for 120 minutes. The reaction mixture is extracted with n-hexane. the extract is washed with water and the solvent is evaporated from the nhexane solution. Removal of volatile materials by evaporation at l20C under l mmHg affords the objective compound (647 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table 1.

EXAMPLE Preparation of the S-containing organic phosphorus compound ll: R R C,H,,; R R H; R CH CH=CH Diisobutylhydroxymethyl phosphonate (448 g) as obtained in Example 4 is admixed with carbon disulfide I52 g). and 25 7: aqueous solution of sodium hydroxide (320 g) is dropwise added thereto while cooling at 20C. The reaction is carried out at 50C for 60 minutes. Further. allyl chloride (I53 g) is added thereto. and the reaction is continued at 50C for 120 minutes. The reaction mixture is extracted with n-hexanc (600 ml) and washed with warm water. By evaporation of volatile materials at l00C under 10 mmHg, there is obtained the objective compound (544 g) as a yellow liquid. The elementary analysis ofthe product is shown in Table 1.

EXAMPLE 6 Preparation of the S-containing organic phosphorus compound [l: R' R R" CH; R" R" H] Diisr butylhydroxymethyl phosphonate (448 g) as obtained in laxample 4 is admixed with carbon disulfide I52 g). and 30 Cl aqueous solution of potassium hydroxide (280 g) is dropwise added thereto while cool ing at 20C. The reaction is carried out at 50C for 60 minutes. Then. sec.'butyl bromide (274 g) is added thereto. and the reaction is carried out at 60C for l50 minutes. The reaction mixture is extracted with nhexane (700 ml). washed with warm water and treated as in Example 3 to give the objective compound (570 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table l.

EXAMPLE 7 Preparation of the S-containing organic phosphorus compound ll: R R CH(CH )CH CH(CH R R H; R C H As in Example 1, there is produced di( 1- isobutylethyl)-hydroxymethyl phosphonate having an acid value of 9.3 (2499 g) by the use of di( 1- isobutylethyl) phosphite (2250 g). paraformaldehyde (purity, 88 7r; 307 g) and tributylamine (50 g).

In a flask equipped with a stirrer. di( 1 -isobutylcthyl hydroxymethyl phosphonate (588 g) is charged, carbon disulfide (152 g) is added thereto, and the resultant mixture is stirred at 20C. After the dropwise addition of 40 aqueous solution of sodium hydroxide (2l0 g), the reaction is carried out at 50C for 60 minutes.

To the reaction mixture, t-butyl chloride (185 g) is added. and the reaction is carried out at 50C for l20 minutes. The reaction mixture is extracted with nhexane (600 ml), the extract is washed with warm water and the solvent is removed from the n-hexane so lution by evaporation. Then, volatile materials are distilled off at I00C under 5 mmHg to give the objective compound as an orange yellow liquid (649 g). The elementary analysis of the product is shown in Table 1.

EXAMPLE 8 Preparation of the S-containing organic phosphorus compound [1: R R CH(CH )CH CH(CH R R H; R CH C HQ Di( l-isobutylethyl)hydroxymethyl phosphonate having an acid value of 9.3 (800 g) as obtained in Example 7 is washed with 0.5 72 aqueous solution of sodium hydroxide (1000 ml) and further three times with hot water (I200 ml). Removal of volatile materials at l00C under 5 mmHg affords di( lisobutylethyl)hydroxymethyl phosphonate having an acid value of 0.4 (744 g). To the thus obtained di( 1- isobutylethyl)hydroxymethyl phosphonate (560 g), carbon disulfide (167 g) is added, and 40 7c aqueous solution of sodium hydroxide (200 g) is dropwise added thereto at 20C while stirring. The reaction is carried out at 50C for 60 minutes. After the addition of benzyl chloride (253 g), the reaction is continued at 50C for minutes. The reaction mixture is extracted with n-hexane (800 ml), the extract is washed with warm water and the solvent is evaporated from the n-hexane solution. Removal of volatile materials by distillation at l l0C under about 5 mmHg affords the objective compound (747 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table l.

EXAMPLE 9 Preparation oi the S-containing organic phosphorus compound [1: R I R CH(CH )CH CH(CH:,). R R H. R CH CH=CH I Di( l-isobutylethyl )hydroxymethyl phosphonate having an acid value of 9.3 (1500 g) as obtained in Example 7 is washed five times with water (2000 m1). and volatile materials are evaporated at 100C under mmHg to give di(1-isobutylethyl)-hydroxymethyl phosphonate having an acid value of 1.1 (1383 g). To the thus obtained di(1-butylthyl)hydroxymethylphosphonate (560 g), carbon disulfide (160 g) is added, and 40 7c aqueous solution of sodium hydroxide (200 g) is dropwise added thereto at 20C while stirring. The reaction is carried out at 50C for 60 minutes. After the addition of allyl chloride (153 g), the reaction is continued at 50C for 120 minutes. The reaction mixture is extracted with n-hexane (700 ml), the extract is washed with warm water and the solvent is evaporated from the n-hexane solution. Removal of volatile materials by distillation at l C under 10 mmHg affords the objective compound (656 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table 1.

EXAMPLE 10 Preparation of the S-containing organic phosphrus compound [1: R' R CH(CH )CH CH(CH R R H; R CH CH=CHCH;,]

In a flask equipped with a stirrer, di( 1- isobutylethyl)hydroxymethyl phosphonate having an acid value of 9.3 (560 g) as obtained in Example 7 is charged, carbon disulfide (182 g) is added thereto, and the resultant mixture is stirred at C. To the resulting mixture, 40 aqueous solution of sodium hydroxide (220 g) is dropwise added, and the reaction is carried out at 50C for 60 minutes. Crotyl chloride (182 g) is added to the resultant mixture, and the reaction is further continued at 60C for 180 minutes. The reaction mixture is extracted with n-hexane (700 ml), the extract is washed with warm water and the solvent is evaporated from the n-hexane solution. By distilling off volatile materials at 1 10C under about 5 mmHg, there is produced the objective compound (633 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table 1.

EXAMPLE [1 Preparation of the S-containing organic phosphorus compound [1: R R CH- CH(C H5)(CH CH R R H; R C H In a flask equipped with a stirrer, di(2-ethylhexyl)- phosphite (918 g) and paraformaldehyde (purity, 92 98 g) are charged, and the resultant mixture is stirred at 1 10 to 120C for 2 hours. The reaction mixture is filtered to give di(2-ethy1hexyl)hydroxymethyl phosphonatc (993 g).

1n a flask equipped with a stirrer, di(2-ethylhexyl) hydroxymcthyl phosphonate (672 g) is charged. carbon disull'ide (152 g) is added thereto, and the resultant mixture is stirred at 20C. While keeping this temperature, 40 ii aqueous solution of sodium hydroxide (200 g) is dropwise added thereto, and the reaction is further continued at 50C for 60 minutes.

8 To the reaction mixture. t-hutyl chloride 185 g) is added, and the reaction is carried out at 50C for 120 minutes. The reaction mixture is extracted with n hexane (900 ml), the extract is washed with warm water and the solvent is evaporated. By distilling ol'l volatile materials at l 10C under about 5 mmHg, there is produced the objective compound (776 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table 1.

EXAMPLE 12 Preparation of the S-containing organic phosphorus compound [1: R 2 CH CH(C H;,)(CH );;CH3; R R H; R CH C H To di(Z-ethylhexyl)hydroxymethyl phosphonatc (672 g) obtained as in Example 1 1, 40 Yr aqueous solu tion of sodium hydroxide (200 g) is dropwise added while stirring at 20C, and then carbon disulfide is portionwise added thereto. The reaction is carried out at 50C for 60 minutes. Then, benzyl chloride (253 g) is added thereto, and the reaction is further continued at 50C for 120 minutes. The reaction mixture is ex' tracted with n-hexane (900 ml), the extract is washed with warm water and the solvent is evaporated. By distilling off volatile materials at 120C under 5 mmHg, there is produced the objective compound (853 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table 1.

EXAMPLE 13 Preparation of the S-containing organic phosphorus compound 11: R R CH C (C2 s)( 2):i s R3 R H; R CH CH=CH To a mixture of di(2-ethylhexyl)hydroxymethyl phosphonate (672 g) as obtained in Example 11 and carbon disulfide 152 g). 40 '7: aqueous solution of so dium hydroxide (200 g) is dropwise added at 20C while stirring, and the reaction is carried out at 50C for 60 minutes. Then, allyl chloride (153 g) is added thereto, and the reaction is further continued at 50C for 120 minutes. The reaction mixture is extracted with n-hexane (900 ml), the extract is washed with warm water and the solvent is evaporated from the n-hcxane solution. By distilling off volatile materials at C under 10 mmHg. there is produced the objective compound (742 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table 1.

EXAMPLE 14 Preparation of the S-containing organic phosphorus compound [1: R R CH- CH(C )(CH CH3l R H; R CH=CHCH R CH- C H l As in Example 1, there is produced di(2-ethy1hexyl a-hydroxycrotyl phosphonate (982 g) by the use of di( 2-ethy1hexyl) phosphite (918 g), crotonaldehyde (210 g) and tributylamine (17 g). The thus produced di(2-ethylhexyl)-a-hydroxycroty1 phosphonate (752 g) is charged in a flask equipped with a stirrer, carbon disulfide is added thereto. and stirring is carried out at 20C. After the dropwise addition of 40 aqueous solution of sodium hydroxide (200 g), the reaction is effected at 50C for 60 minutes. Then. benzyl chloride (253 g) is added to the reaction mixture. and the reaction is continued at 50C for minutes. The reaction mixture is extracted vtith n-hexane 1000 ml), the extract is washed with warm water and the solvent is 9 evaporated from the n-hexane solution. By distilling oll' volatile materials at l lOC under about mmHg. there is produced the objective compound (870 g) as an orange yellow liquid. The elementary analysis of the product is shown in Table l.

The S-containing organic phosphorus compounds [I] prepared in the above Examples are quite stable to chemicals. For instance, the S-containing organic phosphorus compound [l: R R CH(CH )CH CH(CH R R H; R CH C H l as obtained in Example 8 does not show any decomposition even when boiled in water or aqueous hydrochloric acid.

Further. they are relatively stable to heat. For instance. the differential thermal analysis of some S- containing organic phosphorus compounds [I] as obtained in the said Examples affords the results as shown in Table 2.

Table 2 Example Initiation of thermal Appearance of differdegradation tCl ential heat (T) 3 H 2 l 5 5 205 215 7 200 230 8 2H] 225 9 2H) 235 l l 220 265 I2 225 260 I3 235 260 The S-containing organic phosphorus compounds [I] show only a slight toxicity to mammals and are quite safe to human beings and animals. For instance, the acute oral toxicities of the compounds in the foregoing Examples 8 and 12 determined in the test using mice are respectively LD l0.000 ul/kg and LD 6.480 Ll/kg.

The S-containing organic phosphorus compounds [I] of the invention are particularly useful as additives to lubricating oils, such as hydraulic fluids. automatic transmission fluids, internal combustion engine oils and gear oils. which require wearresistant or extreme pressure lubricating properties.

Referring to the hydraulic fluids. in operating hydraulic pumps (particularly vane pumps). the rise of the working pressure and the high speed rotation have given rise to a greater wear between the cam ring and the vane. To provide against this wear. there have been used zinc dialkyldithiophosphates or other sulfurphosphorus extreme pressure additives. Still. however. they are not entirely satisfactory to ensure a long last 10 ing performance under severe operating conditions. nor have fully settled the problems concerning to dis coloration and corrosion of copper alloy bushing.

By the co-use of suitable anti-oxidants. corrosion in hibitors. rust prcventives and the like with the S- containing organic phosphorus compounds [I] of the invention. it is not only possible to prevent more effectively the wear of machinery parts under stern conditions than with conventional lubricating additives but also to improve durability and non-corrosion quality of these pans more than expected.

With regard to internal combustion engine oils. extreme pressure lubricants having nearly satisfactory performance are obtainable by using zinc dialkyldithiophosphates or zinc diaryldithiophosphates coupled with various kinds of detergent-dispersants. ln recent years. however. there has been a new demand for lubricants having lower ash contents. and as there has been a strong requirement of public for saving of resources. it is expected that lubricants should have a longer durability.

The S-containing organic phosphorus compounds [I] of the invention display, by the combination with ashless dispersants, anti-oxidants, detergents, etc.. a function of extreme pressure lubrication equivalent to con ventional internal combustion engine oils which contain zinc dialkyldithiophosphates with a stability to high temperature close to internal combustion engine oils which contain zinc diaryldithiophosphates. Moreover. it is possible to obtain internal combustion engine oils which has a lesser ash content.

In gear oils. the lubrication of gearwheel requires to cover the characteristic factor of the gearwheel which shows especially a high contact load on the friction surfaces where the film of the lubricating oils is apt to break to cause a wear of gear surface or its damage by seizure. Particularly. in the hypoid gears used for the reduction gears in a majority of motor cars and the gearwheels for driving the rolls of rolling mills. table rollers, etc. which sustain a shocking load. the extreme pressure lubricating oils are essentially used for prevention of damage. To meet these requirements various kinds of extreme pressure lubricating compositions have been used since around 1925. However. the recent progress of gear engineering promotes to use smaller gear with high performance, and the gears have increasingly been used under high speed and high horse power conditions. Thus. the rise of the oil temperature has become unavoidable. In the case of motor cars. because of the attachements of catalytic converter mufflers, after-burner mufflers, etc. for emission control, an additional rise of the gear lubricating oil temperature may be at present in excess of C, which is a conventionally accepted temperature limit for the working temperature.

Illustrating the working mechanism of an extreme pressure lubricating oil, it is reacted with a metal at a hot spot of mutually contacting frictional surfaces to produce metal sulfide, chloride, phosphate or the like and to prevent wear or seizure by fusion of the microscopic convex portions of the frictional surface by the action of the film produced. Accordingly, an extreme pressure lubricating oil must react well with steel or its alloy to form a useful inorganic film.

The film should desirably have the properties to adhere to the frictional surface uniformly. thinly and firmly. and also to alleviate the shearing stress in the same way as the solid lubricant. The reaction of the lu- 1 l bricant to the metal surface should not be exerted corrosii t. ly.

There ate known a variety of chemical substances having such extreme pressure lubricating action. For the practical use. however. they should have also some other properties such as corrosion resistance to nonl2 composition for hypoid gears may have a concentration of miirethan 1 percent by weight.

The extreme pressure lubricating properties olsome of the S-containing organic phosphorus compounds [I] as well as those of some conventional extreme pressure additive are shown in Table 3.

Table 3 Test sample" 11$ 4 ball test Shell 4 hall tcst" Copper corrosion T hermal stability IS load llsg] test" test Additive Amount is loud Welding 111C. 3 hrs 121C (hrs) 1% by lkg] load lkgl weight) Product in 1.0 192 I26 178 lb 168 Example 9 2 5 242 I58 224 lb 168 Product in 0.7 242 141 200 (Edwin l6lt Example 8 3.0 293 I58 316 1b Standard 16K Product in 1.0 217 I26 200 and 108 Example 13 3.0 267 I58 282 2a 144 Product in 1.5 141 224 la 168 Example 12 2.5 267 158 251 lb 168 Product in 0.5 197 116 158 in M4 Example 3 2.0 242 141 124 1b I44 Zinc dihexyldithio- 0.7 I67 I12 282 la 168 phosphate 2.0 2 I 7 I26 355 lb 168 Gear oil A 6.5 242 I41 355 2a 168 Gear oilB 7.0 217 I26 316 lb 168 Gear oil C 9.5 267 I41 398 Be 120 Gear oil D 6.3 242 I58 355 2a I44 Note:

The test sample was prepared by adding the additive to a solvent refined base oil SAT. 90. The additive in gear oil A is Anglamol W" t Lu brizol Corp]. The additive in gear oil B is Anglamol 98A" tLubmol Corp). The additnc in gear oil C is "Santupoid 23 RI" [Monsanto Chemical Co I. The additive in gear oil I) is "Hitec 333" (Edwin Cooper & Ctr. Ltd! "115 [Japanese Industrial Standard] K25I'9-67.

'AS'I'M (American Society for Testing and Materials) DZ783-7l.

ASTM DI -68.

Air oven test lthe time until haze or precipitation is produced).

ferrous alloys and rust prevention to steel alloys. Further, they are required to be hardly oxidized or heat decomposed and to be capable of using for several thousand hours or. in case of motor ears, for 100,000 200.000 kilometers.

Most of conventional extreme pressure lubricant compositions are such as has an insufficient stability tp a higher oil temperature even if it has a sufficient performance for extreme pressure lubrication, or. has an unsatisfactory performance of extreme pressure lubrication even if it has a sufficient stability to a higher oil temperature. Most of hypoid gear oils that may be satisfactory in both functions have the limiting oil temperature of nearly 125C durable for the use for 500 1,000 hours or 50,000 100,000 kilometers. Generally. the usable life of lubricants is reduced to half by their temperature rise of about 8- IOC. Accordingly, there are rare extreme pressure gear oils that have a sufficient durability for the uses in which the oil temperature exceeds 135C.

By using an extreme pressure lubricating oil composition comprising the S-containing organic phosphorus compounds [I]. it is possible to use machineries with all the above-described functions satisfied and with a longer durable life even under the condition ofa maximum oil temperature of 170C and an average oil temperature of 135C.

The concentration of the S-containing organic phosphorus compound [I] of the invention in lubricating oil compositions depends primarily upon the type of oil used and the nature of the service to which the lubricating oil compositions are subjected. In most instances. the concentration will range from about 0.1 to about l0.0 percent by weight of the lubricating oil composill'dll. time particularly. for example. a lubricating oil From the above results. it may be understood that the additives of the invention are more excellent than conventional extreme pressure additives not only in extreme pressure lubricating property but also in anticorrosion to copper and thermal stability.

The most characteristic feature of the lubricating oil composition according to the present invention is the inclusion of the S-containing organic phosphorus compound [I]. It is particularly effective to use the said compound together with a hydrocarbon polysulfide or its reaction product with a tertiary phosphite for hypoid gears. Lubricants containing such combination of additivcs are characterized by non-corrosiveness. improved stability against oxidative and thermal degradation. and the ability to provide effective lubrication under such conditions as being exposed to shock load, high speed and high torque.

The substantially hydrocarbon polysulfidcs which are especially useful for this purpose include principally aliphatic. cycloaliphatic and aromatic disulfidcs. trisulfides, tetrasulfides. pentasulfides or higher polysulfides. The term "polysulfidc" as used herein designates compounds in which two substantially hydrocarbon radicals are joined to a group consisting of at least 2 sulfur atoms. Such polysulfides are represented. for the most part. by any of the structural formulas below.

wherein R is a substantially hydrocarbon radical and m is an integer preferably less than 6. The nature of the linkage between the sulfur atoms is not clearly underl3 stood. although it is believed that such linkage may be described by a single covalent bond. at double bond or a coordinate covalent bond.

Polysulfitles preferred for use herein are alkyl poly- 14 preferably alkyl or alkenyl having 8 to l8 carbon atoms.

The amount of the hydrocarbon polysulfide or its reaction product with the tertiary phosphite to be incorsulfides. cycloalkyl polysull'idcs. aralkyl polysulfides. poruted may he usually about 0.5 to about 10 percent aryl polysull'idcs. alkaryl polysulfides or polysullides by weight based on the weight of the lubricating oil. having a mixture of such hydrocarbon radicals. The in place of or in addition to the hydrocarbon polysulpolysulfides containing at least about 6 carbon atoms fide or its reaction product with the tertiary phosphite. per molecule have greater oil solubility and are generthere may be also employed for attaining the substanally preferred. Specific examples of such polysulfides tially same purpose the reaction product of an acid are diisobutyl trisulfide. diisopentyl trisulfide. di-nphosphate and an amine. which is representable by the butyl tetrasulfide. dicyclopentyl disulfide. dimethylcyformula: clohexyl tetrasulfidc. di2-ethylcyclopcntyl disulfide, dipentyl trisulficle. B-pinylpentasulfide, dibenzyl trisul- H fide. benzyl isooctyl disulfide. diphenyl disulfide. cycloa hexyl cyclopentyl trisulfide. a-butyl-B-naphthyl trisultR'0J,.P(0Ht-. ,.N-R"' fide. bistpolyisobutene (molecular weight of 1000)- M. suhstituted-phenyl)-disulfide, ditolyl disulfide, diparaffin wax trisulfide diterpenyl disulfide, bis(o.pl p py plt y lfi dldodecyl msulfidm wherein n is an integer of l or 2, R is an aliphatic hyq'behgnyl f' and lbobutyl cyclohelfyl lctrasul drocarbon group such as alkyl or alkenyl having 6 to I23 fide other poly sulf des such as polar substituted poly- Carbon atoms and H m and H, are each a hydro sulfides are exemplified by di(p-chlorobenzyl)disullidc, gen mum or an aliphatic or aromatic hydrocarbon di(m-bromopentyl)trisulfide, di(p- 25 gmupv provided that at least one of u R!!! and m. butoxyphenyUdisulfide and di(o-mtro-p is not a hydrogen P f'W For the same purpose as above. the said acid phossmcc the poll/humid have generally a tendency phate itself may be used. Also, aliphatic secondary corrode copper and its alloys, such unfavorable propphosphnes of the formula. erty may be eltminated by treatment of them with tertiary phosphites on heating. Such treatment may be also effective in increasing the extreme pressure lubri- 0 cation property. In the treatment, for instance. a polyll IR OzPH sulfide 100 parts by weight) and a tertiary phosphite (5 to 50 parts) may be mixed together at a temperature P T P undcra reduced pressrc Or wherein R is an aliphatic hydrocarbon group such as in an inert gas. tor a period of0.5 to 3 hours. As the ter alkyl or alkenyl hay-mg 10 to 18 Carbon atoms may he tiary phosphite. there may be used the one represented [15mv y the form The results of the tests for the extreme pressure lubrieating property and the non-corrosion property to cop- P per of some lubricating oil compositions comprising the S-containing organic phosphorus compounds [I] and the additives as above are shown in Table 4.

' Table 4 Lubricating oil composition" a h c d r. f g h i 1 l. l Additive ('21 by wcightl stilrurimi olefin 3.0 3.0 2.0 |.0 1.0 HI 1.0 l o "Anglumol 32" lLuhri/ol Corp Sullurixed terpene i 2.0 L0 "Amoco 4K" (Amono Chem I Sulfurized [any oil Luhrwol 500 lLUhfWOI 2.0 .0 2.0 Corp.)

Dihenzyldisulfide 0.5 0.3 Z-Ethylhexyl acid phosphate v V 0.5 (l oleylaniine salt Trilziuryl phosphlte 0,6 0.4 0.3 0.35 0.3 0.2 0.3 Product in lixample 9 l.5 Product in lzxamplc it i 5 l (J 1.5

Product in limmplc l] 1 5 Product in Example 12 L0 1.5 l.5 HS 4 ball test 167 ll? 26? 267 293 I58 267 l67 192 2 2 242 267 [5 load tlsgl Copper corrosion test" 2.1 lb lb lb lb 221 lb la 2a 2a la lb l2lC. 3 hrs \olc "The compootion Wm prepared by adding the tidditnct to .i then! rctined base oil MAI )0 ln case ot the compositions h. c. d. c. i .md 1. the \Ulltlt'llct] olefin and vi herein R. R" and R' are each an aliphatic or am matic hydrocarbon group hming 2 to 18 carbon atoms.

From the above results. it may be understood that the combined use of thc S-containing organic phosphorus erythritol ester, polybutcnylalkylamine. polybutenylhydroxybenzylamine, etc. By the use of such dispersant, sludging or lacquer formation of any component effective for extreme pressure lubrication from the lubricating oil composition at elevated temperatures can be prevented. Many conventional dispersants result in the l depression of the extreme pressure lubrication property when incorporated, but the said dispersant does not afford any material influence on such property and rather improves remarkably the durability to high temperature of the lubricating oil composition. The concentration of the dispersant may he usually from about 5 to about 20 percent by weight based on the combined weight of the S-containing organic phosphorus compound [l] and the hydrocarbon polysulfide or its derivative.

When the S-containing organic phosphorus compound [I] is used as an additive to a lubricating oil for internal combustion engines, it is preferred to incorporate therein. in addition to ashless dispersants, metallic detergents such as neutral or overbasic alkaline earth metal salt of alkylbenzene-sulfonic acid. petroleum sulfonic acid and alkylnaphthalcne-sulfonic acid. neutral or ovcrhasic alkaline earth metal phcnatc of alkyl phenol and sulfurizcd alkylphcnol. neutral or overbasic alkaline earth metal carhoxylate of alkylsalicylic acid. neutral or overbasic alkaline earth metal salt of polybutcnylthiophosphonatc and the like (the alkeline earth metal being usually calcium, barium or magncsium). whereby the corrosive wear due to the acidic material in blow by gas is prevented and the detcrgency and the dispersancy at high temperatures are increased.

The lubricating oil composition of the invention may further contain other additives such as corrosion inhibitors, rust inhibitors, oxidation inhibitors. etc.

Examples of the corrosion inhibitors. particularly effective for copper and its alloys at a temperature higher than l20C, are those having a CNN bond such as benzotriazole and indazole and those having a N=C- S-S bond such as 2-(n-alkyldithio)benzothiazole. 2.5

bis(n-alkyldithio )l .3.4-thiadiazolc. 2.5-bis( N.N- dialkyldithiocarbamyl)-l .3.4-thiadiazole, 2-( nalkyldithio)benzoxazole and 2-( nalkyldithio)benzimidazole. The corrosion inhibitors are effective not only for preventing the corrosion of copper and its alloys but also for suppressing the promotion of the oxidative deterioration of oils due to the copper dissolved therein.

The results as shown in Table 5 indicate the extreme pressure lubricating property and the oxidation stability of some lubricating oil compositions comprising extreme pressure additives, ashless dispersants and corrosion inhibitors.

Table 5 Lubricating oil composition l Additive 4% by weight) Sulfurized olefin 2) Product in Example 8 Product in Example l2 Z-Ethylhexyl acid phosphate coconut amine salt Polyhutenyl succinimidehorate Lubrizol 935 (Luhrizol Corp.)

Polybutenyl succinate "Lubrizol 936 (Lubrizol Ben zotriazole JIS 4 ball test 3) 15 load (kg) Indiana stirring oxidation test 4] Table S-continued Lubricating oil compo- Gear sitinn I m n n p q r s oil Additive ("fr A by weight) n-Pentane insoluble 0.6 0.2 0.4 0.05 0.0S 0.05 (1.1 0.38

Lacquer formation heavy none light none none none none heavy Note 1 The composltion was prepared by adding the additirehl to a solvent refined base oil SAE 90. The gear oil A as control is the same as in Table 3 2 The sulfnri/ed olefin 2 6 or 1.8 parts by weight) was reacted with triisodecyl phosphite (0.4 or (1.2 part by Examples of the rust inhibitors. especially effective for inhibition of the rusting on a steel surface at high humidity conditions without any depression of the extreme pressure lubrication and high temperature stability, are alkyl acid phosphates and their alkylamine salts, alkyl or alkenyl succinic acids and their derivatives, sorbitol fatty acid esters, reaction products of dialkylphosphoric acids with ethylene oxide, etc.

Examples of the oxidation inhibitors, especially effective for increasing the high temperature stability, are hindered bisphenols (e.g. 4.4methylene-bis (2,6-di-tbutylphenol), 4,4-bis(2,6-di-t-butylphenol). 4.4-thiobis(6t-butyl-o-cresol), 2,6-di-t-butyl-adimethylamino-p-cresol), aromatic amines (e.g. anaphthylamine. di-sec.-butyldiphenylamine, p,p'- dioctyldiphenylamine, bis(p-dimcthylamin0phenyl)- methane), zinc dialkyldithiophosphates, dialkyldithiocarbamates (e.g. zinc, cadmium, ammonium, alkyl dialkyldithiocarbamates), etc.

Moreover, any other commercially available additives useful as pour point depressants, antifoaming agents, viscosity index improvers and the like may be incorporated into the lubricating oil composition of the invention.

The lubricating oils in which the S-containing organic phosphorus compound [I] is useful as an additive may be of synthetic, animal, vegetable, or mineral origin. Ordinarily. mineral lubricating oils are preferred by reason of their availability, general excellence, and low cost. For certain applications, oils belonging to one of the other free groups may be preferred. For instance, synthetic polyester oils such as didodecyl adipate and di-2-ethylhexyl sebacatc are often preferred as jet engine lubricants. Normally, the lubricating oils will be 3.0 to 40 cSt in viscosity at 98.89C, more than about 80 in viscosity index, higher than about 180C in flash point and about 250 to 600C in boiling point.

Lubricating oils of mineral origin may be the ones of paraffin, naphthene or mixed type, preferably purified, for instance, by treating with an appropriate solvent such as phenol, propane or furfural to eliminate asphalten and aromatics, treating with activated clay or aluminum chloride to decrease impurities and/or subjecting to hydrogenation or hydrogenolysis to reduce unstable components. Further, those are favorably subjected to dcwaxing in order to improve thc fluidity at low temperature.

Lubricating oils of synthetic origin may be, for instance, polymerized oils of aolefins, polyisobutylcne. synthetic hindered esters (e.g. dipentaerythritol ester,

trimethylolpropane ester), polyethers (e.g. polypropylene glycol), etc. These are preferred to have a stability at higher temperature.

Practical and presently preferred examples of the lubricating oil composition according to the present invention are shown below. Parts are by weight.

EXAMPLE A The S-containing organic phosphorus compound [1: R R CH(CH )CH CH(CH R R H; R CH C H (3.0 parts) is incorporated into a mineral oil SAE (viscosity index. (97.0 parts) to give a gear lubricating oil composition.

EXAMPLE B The S-containing organic phosphorus compound [1: R R =CH (CH CH R" R H; R =CH- C H (1.5 parts, aolefin polysulfides containing C H S as a major component (2.0 parts) and triisodecyl phosphite (0.4 part), zinc diamyldithiocarbamate (0.3 part), decyl acid phosphate (0.2 part), polybutenylsuccinimide-boron compound Lubrizol 935" (Lubrizol Corp.) (0.35 part) and polymerized alkylsiloxanc DC-A" (Dow Corning Corp.) (0.003 part) are incor' porated into a mineral oil SAE 90 to make a total weight of parts, whereby a gear lubricating oil composition is obtained.

EXAMPLE C The S-containing organic phosphorus compound [1: R'= R CH CH(C H )(CH CH R R H', R CH C H I (3.0 parts), polybutenyl hydroxybenzylamine Amoco 9250" (Amoco Chem.) (0.6 part), 2.5- bis(t-octyldithio)-1,3,4-thiadiazole (0.2 part), sorbitan monooleate (0.3 part) and polymerized methacrylate Plexol (Rohm & Haas Co.) (0.1 part) are incorporated into a mineral oil SAE 80 to make a total weight of 100 parts, whereby a gear lubricating oil composition is obtained.

EXAMPLE D The S-containing organic phosphorus compound ll: R1: R2 =CH2CH(C2H5)(CH2 )gC ili R R4 H; R5 CH C H5] (LO part), polybutenyl succinimide Lu brizol 890" (Lubrizol Corp.) (30 parts), overbasic barium nonylnaphthalencsulfonate NA-SuhBSB" (R.T. Vanderbilt Co, Inc.) (10 part), dodecenylsuccinic anhydride (0.] part). polymerized methacrylatc Plexol 732" (Rohm & Haas Co.) (7.5 parts) and poly mcrized alkylsiloxane DC-A (Dow Corning Corp.)

19 0.01:; parlt are incorporated into a 100 neutral oil to nakc a total weight of 100 parts. whereby a gasoline ntcrnal combustion engine lubricating oil (SAE lW- l0) composition is obtained.

EXAMPLE E The S-containing organic phosphorus compound [1: l R CH CH(C H (CH CH R R H; R 1 YH CH CHH (2.0 parts). Z-ethtlhexyl acid phosphate )lcylamine salt (05 part). polybutenyl succinate Lu- )rizol 948 (Lubrizol Corp.) (0.4 part). benzotriazole 0.05 part), p-octylphenylphenylamine (0.3 part). dolecyl acid phosphate (015 part) and polymerized alzylsiloxane DC-A (Dow Corning Corp.) (0.001 part) ire incorporated into a mineral oil SAE 90 to make a otal weight of 100 parts, whereby a gear lubricating oil :omposition is obtained.

EXAMPLE F The S-containing organic phosphorus compound [l1 {1: R CH(CH )CH CH(CH R R H; R :H CH=CH (2.5 parts), polybutenyl succinimide Oloa IZOON (Chevron chemicals) (0.3 part). 2,6-di- -butylo-dimethylamino-p-cresol (03 part). sulfurized )lefin Anglamol 32" (Lubrizol Corp.) (0.5 part), inlazole (0.03 part) polymerized methylsiloxane DC-A Dow Corning Co.) (000] part) and calcium petro eum sulfonate Petrobase 210 (Penreco Inc.) (0.8 wart) are incorporated into a mineral oil SAE l40 to nake a total weight of 100 parts, whereby a gear lubrirating oil composition is obtained.

EXAMPLE G The S-containing organic phosphorus compound [1: l R CH CH(C H,t-,)(CH CH R R H; R fH C H 1.5 parts), polybutenyl succinic acid penta- :rythritol ester Lubrizol 936 (Lubrizol Corp.) (0.4 iart), dibenzyl disulfide (0.5 part). p.p'- lioctyldiphenylamine (0.3 part), benzotriazole (0.03 llll't).21 treated product of sulfurized fatty oil Lubrizol 006" (Lubrizol Corp.) parts) with trilaury] phos- Ihite (0.4 part) at lC for 40 minutes and lauryl acid ihosphate (0.! part) are incorporated into a mineral ii] SAE 90 to make a total weight of 100 parts. whereby a gear lubricating oil composition is obtained.

EXAMPLE H The Scontaining organic phosphorus compound [l: t R CH(CH;,)CH CH(CH R R H; R'' :H2C5H5] (2.0 parts), polybutenyl succinimide "Hitee 5636" (Edwin Cooper & Co.. Ltd.) (04 part). a reated product of sulfurized olefin "Hitec E053 Edwin Cooper & Co. Ltd.) (2.0 parts) with triisooctyl hosphite (0.4 part) at 130C for 30 minutes, p-octyl henylphenylamine (0.4 part), benzotriazole (0.05 art), octadecenyl succinic acid anhydride (0.l part) nd carboxylic ester Lubrizol 859 (Lubrizol Corp.) 0.] part) are incorporated into a mineral oil SAE 80 to take a total weight of lO0 parts, whereby a gear lubriating oil composition is obtained.

EXAMPLE I The S-containing organic phosphorus compound ll: R CH CH(C H5)(CH CH"; R R H; R H- C H I (0.7 part). polybutenyl hydroxybenzylamine .moco 9000 (Amoco Chem.) (0.5 part). Z-methyl-S- inylpyridine-alkyl methacnlate copolymer ECA- 531- (Exxon Chemicals) (5.0 parts).

20 p.p'-dioctyldiphenylamine (0.4 part l and dilauryl phosphite (0.5 part) are incorporated into a I00 neutral oil to make a total weight ol llll) parts. whercb a lubricating oil composition for automatic transmission fluid is obtained.

EXAMPLE J the S-containing organic phosphorus compound [I:

R CH CH(C ,H )(CH );,CH;,; R" I R H; R CH C,.H (0.6 part). calcium didodecylbenzenesulfonate (3 parts). overbasic calcium phenate Oloa 219"" (Chevron Chemicals) (2 parts) and polymerized meth acrylate Plexol l50" (Rohm & Haas Co.) (0.2 part) are incorporated into a mineral oil SAE 30 to make a total weight of 100 parts. whereby a diesel engine lubricating oil composition is obtained.

EXAMPLE K The S-containing organic phosphorus compound ll:

R CH- CH(C H )(CH CH R R H; R CH C H (2.0 parts). dibenzyl disulfide (035 part). polybutenylhydroxybcnzylaminc Amoco 9250" (Amoco Chemicals) (0.45 part). dilauryl hydrogen phosphite (0.4 part). decyl acid phosphate (015 part). benzotriazole (003 part). polymerized alkylsiloxane DC-A (Dow Corning Corp.) (0.001 part). 4.4- methylenebis(2,6-di-t-butylphenol) (0.4 part) and polymerized methacrylate Plexol I50 (Rohm & Haas Co.) (0.] part) are incorporated into a mineral oil SAE to make a total weight of [00 parts. whereby a gear lubricating oil composition is obtained.

EXAMPLE L The S-containing organic phosphorus compound [1: R R" CH CH(C H )(CH );,CH R R H; R CH C H (l.0 part), 2,6di-t-butyl-p-cresol (0.4 part), zinc diamyldithioearbamate (0.2 part), carboxylic ester Santolube 70A" (Monsanto Chem. Co.) (0.03 part), benzotriazole (0.02 part). polymerized methacrylate Plexo] [50 (Rohm & Haas Co.) (0.l part) and polymerized alkylsiloxane DC-A (Dow Corning Corp.) (000] part) are incorporated into a 150 neutral oil to make a total weight of I00 parts, whereby a lubricating oil composition for antiwear hydraulic fluid is obtained.

EXAMPLE M The S-eontaining organic phosphorus compound [1:

R =CH CH(C H .-,)(CH CH R" R H; R CH C H I (1.3 parts) p-octylphenylphenylamine (0.5 part). carboxylic ester Santolube 70A (Monsanto Chem. Co.) (0.05 part). benzotriazole (0.03 part). polymerized methacrylate Plexol 150 (Rohm & Haas Co.) (0.l part) and polymerized alkylsiloxane DC-A (Dow Corning Corp.) (0001 part) are incorporated into a 150 neutral oil to make a total weight of parts. whereby a lubricating oil composition for antiwear hydraulic fluid is obtained.

The lubricating oil compositions as prepared in the above Examples were subjected to various tests for practical utilization. The results are shown in Tables 6 and 7.

IS load (kg! Table h-continued LUI'IIPtIsIlIUIt I I II I: (j H K Shell 4 lull tcsl ll ISIoudlkg) I58 I4I I41 I30 I78 Welding Ioadtkg) 355 355 355 M6 398 LWI 1kg) 68.2 6! J 64.5 63.2 72.6

Timkcn test 4) ()K \ltlllk l lb) 40 45 55' 40 40 lAltest SI failure loud I25 I30 I35 I20 I30 6000 rpm. 90C lhI I40 I35 I50 I30 I50 Copper corrosion test 6) lb lb 2a 2b Ia I2IC 3 hrs.

Steel corrosion test 7) pass pass pass pass pass Rust preventing test R) pass pass pass pass pass I92 hrs.

Humidity cabinet test 9) A B A B A I hr Falcx pin corrosion test I0) pass pass pass fail pass Indiana stirring oxidation test I l I I50C. 48 hrs.

Viscosity increase 7.2 8.4 7.7 9.2 5.4 37.8% I); I

n Pcntanc insoluble (/2 0.08 (H5 (H4 (H6 005 by weight) Lacquer tnrmatiun none trace trace light none Steel strip surface clear clear clear hlack clear (u strip -dark black black surface brown and dark and light black light brown light brown spot flaked flaked Gear Gear Gear Gear oil A oil B oil C oil D 242 2 l 7 267 242 I4I I26 I4I I58 355 .Ilh 39K 355 62.7 58.9 73.8 70.2 45 40 50 45 I30 I25 I40 I40 I45 I 35 I 50 I40 2a Ih 20 2a pass pass Iail pass pass pass pass pass B A C B horderline pass I'ail pass lail 9 4 8 7 I6 I 6.5 (I 38 0.05 I 7| 0 20 hum none heavy medium black brown light lacquer clear sludge sludge black lilnck black bruvin illld Items hunt tarnish flaked flaked llaked sun I I lIIL LUILIHMIIIHIIN IS I Table 6 Notescontinued III I \ample II. I .(i. H and K Ilie gear ml II. t and I) are the aint a -l.llL\l in lal lc 1 IP llnstilutlun ul' Petroleum) lhhmtt bl ASTM Dlf tI-bK III ASrM Dobybli l I I .03 KZSIJJZ Concerning to the \rscosil increa e and the n-pentanc insolu hle. reference is made to ASTM D445 73 and ASTM [1893 69. respeuuwlt Table 7 Lubricating oil composition 1 L M X Y 4 Ball wear test scar diameter 2) 0.38 0.40 0.41 0.42 (mm) Turbine oil uxidiation stability 3) 200t) 3000 2000 2000 [hrs to TAV 2.0 mgKOH/g) Vickers 105C pump test 4) Cam ring wear (mg) I00 hrs I6 20 30 I7 250 hrs 26 29 45 28 I500 hrs 58 78 I I0 I80 4 Ball EP test 5) IS load (kg) I I2 I I2 I00 80 Weld load )0 224 200 I78 (kg) Cu corrosion test 6) lb 2a lb 2b C. I000 hrs Turbine oil rust test 7) pass pass pass pass Emulsion test 8) 40-40-0 38-40 2 40-40-0 38-38-4 (mltminII (I5) (25) (20) Note I I The compositions l. and M correspond respectively to those as prepared in Ex amples l. and M. The composition X was prepared by incorporating LIII'IC dtalkyldi thiophosphat: "Ultra 267" (Chevron Chermcalsl I I.5 .4 lfi di-l-hulyhpm [950! I I (I '1') and earhoxylic ester "Santolubc 70A" (Monsanto Chem Co.) (0.05 I I into a I50 neutral oil The composition Y was prepared by incorporating a sulfurhusphorus extreme pressure additive "Lubriml SIOS" ILuhn/ol Corp.) (3 ll into a I50 neutral oil.

2) ASTM 02266-72,

3) ASTM D MS-fall.

7) ASTM 0665-68.

8) ASTM D1401 72.

From the above test results, it is understood that the lubricating oil compositions according to this invention show excellent properties for the practical utilization.

What is claimed is:

I. A sulfur-containing organic phosphorus compound of the formula:

23 wherein R. R and R are each a hydrocarbon group and R and R are each a hydrogen atom or a hydrocarbon group having not more than 12 carbon atoms.

2. The sulfur-containing organic phosphorus compound according to claim 1, wherein R and R are each an alkyl group having not more than 12 carbon atoms, R and R are each a hydrogen atom and R is a phenylalkyl group having not more than 12 carbon atoms.

3. The sulfur-containing organic phosphorus compound according to claim 2, wherein R and R are each an ethyl group, R and R are each a hydrogen atom and R is a benzyl group.

4. The sulfur-containing organic phosphorus compound according to claim 2. wherein R and R are each an n-buty] group. R" and R are each a hydrogen atom and R is a benzyl group.

5. The sulfur-containing organic phosphorus compound according to claim 2, wherein R and R are each a secondary hexyl group, R and R are each a hydrogen atom and R is a benzyl grooup.

6. The sulfur-containing organic phosphorus compound according to claim 2, wherein R and R are each a 2-ethylhexyl group. R and R are each a hydrogen atom and R is a benzyl group.

7. The sulfur-containing organic phosphorus compound according to claim 1, wherein R and R are each an alkyl group having not more than 12 carbon atoms. R and R are each a hydrogen atom and R is an alkenyl group having not more than 12 carbon atoms.

8. The sulfur-containing organic phosphorus compound according to claim 7, wherein R and R are each an n-butyl group, R and R are each a hydrogen atom and R" is an allyl group.

9. The sulfur-containing organic phosphorus compound according to claim 7, wherein R and R are each a secondary hexyl group, R and R are each a hydrogen atom and R is an allyl group.

[0. The sulfur-containing organic phosphorus compound according to claim 7, wherein R and R are each a secondary hexyl group. R and R are each a hydrogen atom and R is a crotyl group.

I]. The sulfur-containing organic phosphorus compound according to claim 7, wherein R and R are each a 2-ethylhcxyl group. R" and R are each a hydrogen atom and R is an allyl group.

12. The sulfur-containing organic phosphorus compound according to claim 1, wherein R. R and R are each an alkyl group having not more than 12 carbon atoms and R and R are each a hydrogen atom.

13. The sulfur-containing organic phosphorus compound according to claim 12, wherein R and R are each an n-hutyl group, R and R are each a hydrogen atom and R is a sec-butyl group.

14. The sulfur-containing organic phosphorus compound according to claim 12, wherein R and R are each a secondary hexyl group. R and R are each a hydrogen atom and R is a tertiary butyl group.

15. The sulfur-containing organic phosphorus com pound according to claim [2, wherein R and R are each a Z-ethylhexyl group, R and R are each a hydrogen atom and R is a tertiary butyl group.

16. The sulfur-containing organic phosphorus compound according to claim 1, wherein R and R are each an alkyl group having not more than 12 carbon atoms. R is a hydrogen atom. R is an alkenyl group having not more than 12 carbon atoms and R is a phenylalkyl group having not more than 12 carbon atoms.

17. The sulfur-containing organic phosphorus compound according to claim 16, wherein R and R are each a 2-ethylhexyl group, R is a hydrogen atom. R is a crotyl group and R is a benzyl group.

18. The sulfur-containing organic phosphorus compound according to claim 1, wherein R. R. R and R are each an alkyl group having not more than 12 carbon atoms and R is an alkenyl group having not more than 12 carbon atoms.

19. The sulfur-containing organic phosphorus com pound according to claim [8, wherein R, R and R are each an ethyl group. R is a methyl group and R is an allyl group.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,901 932 DATED August 26, 1975 INVENTOR(S) 1 FuSaO Tada et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the official Letters Patent columns 23 and 24 appear before columns 21 and 22. The columns of the Letters Patent are to be read in their numerical order.

Claim 5, line 4 "grooup should read -group-.

Signed and Sealed this eleventh 0; November 1975 [SEAL] A (test:

RUTH C. MASON r-trreslr'ng Officer 

1. A SULFUR-CONTAINING ORGANIC PHOSPHORUS COMPOUND OF THE FORMULA:
 2. The sulfur-containing organic phosphorus compound according to claim 1, wherein R1 and R2 are each an alkyl group having not more than 12 carbon atoms, R3 and R4 are each a hydrogen atom and R5 is a phenylalkyl group having not more than 12 carbon atoms.
 3. The sulfur-containing organic phosphorus compound according to claim 2, wherein R1 and R2 are each an ethyl group, R3 and R4 are each a hydrogen atom and R5 is a benzyl group.
 4. The sulfur-containing organic phosphorus compound according to claim 2, wherein R1 and R2 are each an n-butyl group, R3 and R4 are each a hydrogen atom and R5 is a benzyl group.
 5. The sulfur-containing organic phosphorus compound according to claim 2, wherein R1 and R2 are each a secondary hexyl group, R3 and R4 are each a hydrogen atom and R5 is a benzyl grooup.
 6. The sulfur-containing organic phosphorus compound according to claim 2, wherein R1 and R2 are each a 2-ethylhexyl group, R3 and R4 are each a hydrogen atom and R5 is a benzyl group.
 7. The sulfur-containing organic phosphorus compound according to claim 1, wherein R1 and R2 are each an alkyl group having not more than 12 carbon atoms, R3 and R4 are each a hydrogen atom and R5 is an alkenyl group having not more than 12 carbon atoms.
 8. The sulfur-containing organic phosphorus compound according to claim 7, wherein R1 and R2 are each an n-butyl group, R3 and R4 are each a hydrogen atom and R5 is an allyl group.
 9. The sulfur-containing organic phosphorus compound according to claim 7, wherein R1 and R2 are each a secondary hexyl group, R3 and R4 are each a hydrogen atom and R5 is an allyl group.
 10. The sulfur-containing organic phosphorus compound according to claim 7, wherein R1 and R2 are each a secondary hexyl group, R3 and R4 are each a hydrogen atom and R5 is a crotyl group.
 11. The sulfur-containing organic phosphorus compound according to claim 7, wherein R1 and R2 are each a 2-ethylhexyl group, R3 and R4 are each a hydrogen atom and R5 is an allyl group.
 12. The sulfur-containing organic phosphorus compound according to claim 1, wherein R1, R2 and R5 are each an alkyl group having not more than 12 carbon atoms and R3 and R4 are each a hydrogen atom.
 13. The sulfur-containing organic phosphorus compound according to claim 12, wherein R1 and R2 are each an n-butyl group, R3 and R4 are each a hydrogen atom and R5 is a sec.-butyl group.
 14. The sulfur-containing organic phosphorus compound according to claim 12, wherein R1 and R2 are each a secondary hexyl group, R3 and R4 are each a hydrogen atom and R5 is a tertiary butyl group.
 15. The sulfur-containing organic phosphorus compound according to claim 12, wherein R1 and R2 are each a 2-ethylhexyl group, R3 and R4 are each a hydrogen atom and R5 is a tertiary butyl group.
 16. The sulfur-containing organic phosphorus compound according to claim 1, wherein R1 and R2 are each an alkyl group having not more than 12 carbon atoms, R3 is a hydrogen atom, R4 is an alkenyl group having not more than 12 carbon atoms and R5 is a phenylalkyl group having not more than 12 carbon atoms.
 17. The sulfur-containing organic phosphorus compound According to claim 16, wherein R1 and R2 are each a 2-ethylhexyl group, R3 is a hydrogen atom, R4 is a crotyl group and R5 is a benzyl group.
 18. The sulfur-containing organic phosphorus compound according to claim 1, wherein R1, R2, R3 and R4 are each an alkyl group having not more than 12 carbon atoms and R5 is an alkenyl group having not more than 12 carbon atoms.
 19. The sulfur-containing organic phosphorus compound according to claim 18, wherein R1, R2 and R4 are each an ethyl group, R3 is a methyl group and R5 is an allyl group. 